Limelights have been taken into an e-book since it is light-weight and thin compared to an existing heavy and easy-to-carry paper book and if only storage capacity fully provided, almost library-level material may be carried on and read.
A recent e-book is not limited to a simple character-reading function, and can output pictures and images at the same time as a sound and voice outgoing in order to give audio-visual complacency to users.
The e-book outputs voice and sound through a speaker mounted on a main body case, and in order to enhance the output effect of the speaker, provides a separate soundbox for use in a state of the soundbox being mounted on a speaker.
In a general structure of the e-book, a display panel outputting photographs, figures, pictures, etc. is mounted on a main body case embedded with a circuit substrate provided with various kinds of components, and a keypad assembly inputting a user command is disposed at one side of the display panel.
The speaker is unavoidably mounted on one side or both sides of a keypad assembly as a general e-book arrangement structure, and if the keypad assembly occupying area is reduced for the mounting of the speaker, causing inconveniencies of an operation, the entire size of the e-book becomes larger in the end.
At this time, because the soundbox is manufactured in a die to be mounted separately of the main body case, a width of each side of the keypad assembly becomes as much wider as a space where the soundbox is occupied.
To improve such problems, in a case the soundbox is mounted at both sides of the keypad assembly by substantially decreasing the area of the keypad assembly while keeping the size of the display panel and the main body case as it is, an end part shape of a circuit substrate mounted on the main body case is complicated.
Further, in a case the speaker is mounted around the back surface of the circuit substrate and finished by the main body case while omitting the soundbox occupying space, an output efficiency of sound and voice deteriorates.